Beaverhead County, the City of Dillon, and the Town of Lima have been working with the Federal Emergency Management Agency (FEMA) and Montana Department of Natural Resources and Conservation (DNRC) to update and produce new floodplain maps for the Beaverhead River, Blacktail Deer Creek, Selway Slough and Junction Creek areas, and the Big Hole River.

Many of the existing floodplain maps are based on data from the late 1970s.  Updated Flood Insurance Rate Maps will provide more accurate, current, and detailed data and mapping of flood risk areas. When finalized, the new maps could have effects on some property owners in mapped floodplains (see Floodplain FAQs for more information).

View Preliminary Floodplain Maps

View individual preliminary maps and reports here: Maps & Technical Reports

Appeal and Comment Period: June 9 - September 7, 2021

The 90-day Appeal and Comment Period for the preliminary maps and study will be open until September 7, 2021.  To submit comments or appeals see:  

Appeal & Comment Form
Appeal & Comment Information Sheet 
FEMA Appeal Process Summary Information
FEMA Appeal & Comment Guidance
FEMA Criteria for Submitting Appeals (supplemental info)

Get more information on floodplain designations referenced on the maps:

100-Year Floodplain
Floodway (within the 100-Year Floodplain)
500-Year Floodplain

Newly Mapped into a 100-Year Floodplain on the preliminary maps?  See Low Cost Insurance Options

Big Hole River Floodplain Maps

A flood study and floodplain maps for the Big Hole River were produced in 2015. These and other existing Big Hole River floodplain maps have been incorporated into Preliminary FEMA floodplain maps. They will go through an official 90 day comment and appeal period along with the rest of Beaverhead County's floodplain maps (estimated mid 2021).  An informational meeting for the Big Hole River Preliminary maps was held on February 17, 2021. See below for more information.

Public Meetings

February 17, 2021  -  The Big Hole Watershed Committee hosted a virtual meeting for landowners.  View meeting materials:  Presentation Slides  Big Hole 100 year Floodplain  Low Cost Insurance Options  Comment and Appeal process. 

January 21, 2021 - Beaverhead County, Dillon and Lima hosted a virtual public open house for landowners.  View meeting materials:  Presentation Recording (YouTube)   Presentation Slides   100-Year Floodplain   Floodway (within the 100-Year Floodplain)   500-Year Floodplain    Low Cost Insurance Options   Comment and Appeal Process

In 2019, Beaverhead County, Dillon, and Lima hosted two Public Open Houses to help property owners review the initial draft maps.  The meetings were held:  May 9, 2019 (in Dillon) and May 13, 2019 (in Lima).  View materials from the 2019 meetings:  Dillon Presentation   Lima Presentation   News Coverage   100-Year Floodplain   Floodway   500-Year Floodplain   Low Cost Insurance Options

Come back for more information

We will update this website with new, relevant information as this project progresses.